This invention relates to projection type television viewing systems, and particularly to such systems employing a single cathode ray tube. The invention more particularly relates to apparatus for increasing the image brightness and controlling the orientation of the beam spot in the cathode ray tube.
In conventional projection type television viewing systems three cathode ray tubes are employed each providing an image of a different primary color for projection onto a large screen where the images blend into a composite color image. Although the brightness level of the composite image is satisfactory, the separate color images must be accurately in registry with each other. However, the registration problem is difficult to solve because of instability in the performance of the individual image forming systems.